Stud Welding Technologies in Shipbuilding
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Transcript Stud Welding Technologies in Shipbuilding
Copyright © Nelson Stud Welding, Inc.
Aluminum Stud Welding
Technologies
By Chris Hsu and Clark Champney
Nelson Stud Welding, Inc.
May 10-11, 2011
2011 AWS Conference and Exhibition Welding in Shipbuilding
1
Copyright © Nelson Stud Welding, Inc.
Challenges
Low melting point
High thermal
conductivity
Tough oxide (3488F)
Spatter
Softening
May 10-11, 2011
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Drawn Arc Stud Welding 101
A.
Pilot
Arc
B.
C.
D.
Lift
Plunge Remove
Main Arc
Chuck
May 10-11, 2011
3
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Capacitor discharge
AWS Seattle May 10, 2011
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CD welding Process
Weld time
Timing tip
Plunge speed
Current
Cap voltage
Cable impedance
Contact
Gap
Stored Arc
May 10-11, 2011
2011 AWS Conference and Exhibition Welding in Shipbuilding
5
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MIL specifications
MIL-S-24149/2D:
aluminum stud and
ferrule for drawn arc
MIL-S-24149/5C:
aluminum stud for
CD and stored arc
AWS Seattle May 10, 2011
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Gun accessories
Gas foot
Tranquil arc plunge
dampener
Motorize gun
AWS Seattle May 10, 2011
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plate thickness to stud
diameter ratio
Develop full strength
Steel: 1/3
Aluminum (Al is annealed in stud welding)
½ for drawn arc
¼ for CD
AWS Seattle May 10, 2011
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Weld strength: tensile/torque
AWS Seattle May 10, 2011
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Internally threaded studs
Diameter ¼” to ½”
Threads #10-24
thru ½-13
5000 series alloy
used for stud
(Magnesium based)
LNG tankers
AWS Seattle May 10, 2011
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Pulse cleaning and welding
Cut oxide, rust, oil,
mill-scale
Reduce heat input
backside marking
Stiffen arc
Out of position
Angle iron
Aluminum
Peak: cathodic clean
Background: heat
May 10-11, 2011
Stud Welding Technologies – ShipTech 2011
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Process monitor & logger
Weld energy
Stud hang-up
Cold plunge
Cable overheat
Weld Pass / Fail
Production log
Normal
Cold
Hot
Hang-up
May 10-11, 2011
Welder, Gun and Cable
Stud Welding Technologies – ShipTech 2011
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Copyright © Nelson Stud Welding, Inc.
Summary
CD - contact, gap and stored arc
Drawn arc
Pulse
AC
Up to ½” can be welded down hand and plate vertical
Inverter to weld 5/8” and ¾” in flat position
Process monitor
Drawn arc
CD
May 10-11, 2011
2011 AWS Conference and Exhibition Welding in Shipbuilding
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